查看“Python案例：我的日期类MyDate(二）”的源代码

==案例描述==

我们已经编写过MyDate的日期类，再增加时分秒的数据，派生出日期时间类MyDateTime。

==案例分析==

 <nowiki>class MyDate:
    def __init__(self,y,m,d):
    ......
 
class MyDateTime(MyDate):
    def __init__(self,y,mo,d,h,mi,s):
    ......</nowiki>

==代码==
 <nowiki>
class MyDate:
    __months=[0,31,28,31,30,31,30,31,31,30,31,30,31]
    def __init__(self,y,m,d):
        if y<0:
            raise Exception("无效年份")
        if m<1 or m>12:
            raise Exception("无效月份")
        if y%40==0 or y%4==0 and y%100!=0:
            MyDate.__months[2]=29
        else:
            MyDate.__months[2]=28
        if d<1 or d>MyDate.__months[m]:
            raise Exception("无效日期")
        self.year=y
        self.month=m
        self.day=d
    def show(self,end='\n'):
        print("%04d-%02d-%02d" %(self.year,self.month,self.day),end=end)

class MyDateTime(MyDate):
    def __init__(self,y,mo,d,h,mi,s):
        MyDate.__init__(self,y,mo,d)
        if h<0 or h>23 or mi<0 or mi>59 or s<0 or s>59:
            raise Exception("无效时间")
        self.hour=h
        self.minute=mi
        self.second=s

    def show(self):
        MyDate.show(self,end=" ")
        print("%02d:%02d:%02d" %(self.hour,self.minute,self.second))

if __name__ =="__main__":
    try:
        d=MyDateTime(2017,7,8,23,12,34)
        d.show()
    except Exception as e:
        print(e)




</nowiki>

结果：

2017-07-08 23:12:34